碳对高强度奥氏体焊条熔敷金属冲击韧性的影响  

Effect of carbon on impact toughness of metal deposited with high strength austenite electrodes

作　　者：薛钢[1] 赵福辰[1] 荆艳红 牛继承[1] 张永辉[1] 盖登宇[3] 

机构地区：[1]洛阳船舶材料研究所,河南洛阳471039 [2]河南柴油机重工有限责任公司,河南洛阳471039 [3]哈尔滨工程大学材料科学与化学工程学院,哈尔滨150001

出　　处：《焊接学报》2009年第8期89-92,117,共4页Transactions of The China Welding Institution

摘　　要：对系列碳含量的高强度奥氏体焊条熔敷金属冲击韧性进行了试验,采用扫描电子显微镜对冲击断口和金相磨面的微观形貌进行了分析,结合X射线能谱仪和透射电子显微镜对其中第二相的成分和结构进行了确定,并采用热力学软件Thermo-Calc对凝固相的组成及其中第二相的含量进行了计算.结果表明,冲击韧性随碳含量的增加而线性降低,主要原因在于随着碳含量的增加,在凝固末期形成于奥氏体枝晶间的碳化物由颗粒状变为层片状,尺寸和含量均相应增大,减弱了基体的连续性,同时由于自身的脆性破碎导致裂纹低能扩展,使冲击韧性降低.The impact toughness of metal deposited by high strength austenite electrodes with different carbon content was tested.The microstructure of the impact fractures and the eroded samples were analyzed by SEM.The second-phase was analyzed with the energy spectrometer and the TEM.The solidifying phases and the content of second-phase were calculated with the thermodynamic simulation software.The results indicate that the impact toughness reduces with the carbon increasing.The main cause is that the increasing of carbon content induces the shape changing from particles to slices,the dimension and the content increasing of the carbides forming in the solidification.The carbides weaken the continuity of the austenite base.And the brittle carbides crash easily in the crack spreading.These reduce the impact toughness of the deposited metal.

关 键 词：碳 奥氏体 碳化物 冲击韧性 

分 类 号：TG113[金属学及工艺—物理冶金]